I’ve been making these past couple days and now it has reached to point where I would really need some constructive criticism so I could improve on these. Any help is appreciated! 
First thing, why are the screens reflecting light?
A lot of projected shadows implicate a lot of different colored light sources, this makes it look unrealistic in my opinion.
There is something wrong with the base of the chair which in this case would fall over.
Go more into detail with the materials of the amplifier, the loudspeaker and the chair.
I would put the feet of the sideboard under the draws so the weight goes directly into the floor.